am ea1b1d48: Merge "logd: institute getGroups for socket credentials" (a931cf07) · Commits · e / os / android_system_core

logd/CommandListener.cpp

+7 −9

Original line number	Diff line number	Diff line
		/*
		* Copyright (C) 2012-2013 The Android Open Source Project
		* Copyright (C) 2012-2014 The Android Open Source Project
		*
		* Licensed under the Apache License, Version 2.0 (the "License");
		* you may not use this file except in compliance with the License.
		@@ -24,10 +24,11 @@
		#include <sys/socket.h>
		#include <sys/types.h>

		#include <sysutils/SocketClient.h>
		#include <private/android_filesystem_config.h>
		#include <sysutils/SocketClient.h>

		#include "CommandListener.h"
		#include "LogCommand.h"

		CommandListener::CommandListener(LogBuffer buf, LogReader /reader/,
		LogListener * /swl/)
		@@ -62,9 +63,7 @@ CommandListener::ClearCmd::ClearCmd(LogBuffer *buf)

		int CommandListener::ClearCmd::runCommand(SocketClient *cli,
		int argc, char **argv) {
		if ((cli->getUid() != AID_ROOT)
		&& (cli->getGid() != AID_ROOT)
		&& (cli->getGid() != AID_LOG)) {
		if (!clientHasLogCredentials(cli)) {
		cli->sendMsg("Permission Denied");
		return 0;
		}
		@@ -75,7 +74,7 @@ int CommandListener::ClearCmd::runCommand(SocketClient *cli,
		}

		int id = atoi(argv[1]);
		if ((id < LOG_ID_MIN) \|\| (id >= LOG_ID_MAX)) {
		if ((id < LOG_ID_MIN) \|\| (LOG_ID_MAX <= id)) {
		cli->sendMsg("Range Error");
		return 0;
		}
		@@ -85,7 +84,6 @@ int CommandListener::ClearCmd::runCommand(SocketClient *cli,
		return 0;
		}


		CommandListener::GetBufSizeCmd::GetBufSizeCmd(LogBuffer *buf)
		: LogCommand("getLogSize")
		, mBuf(*buf)
		@@ -99,7 +97,7 @@ int CommandListener::GetBufSizeCmd::runCommand(SocketClient *cli,
		}

		int id = atoi(argv[1]);
		if ((id < LOG_ID_MIN) \|\| (id >= LOG_ID_MAX)) {
		if ((id < LOG_ID_MIN) \|\| (LOG_ID_MAX <= id)) {
		cli->sendMsg("Range Error");
		return 0;
		}
		@@ -124,7 +122,7 @@ int CommandListener::GetBufSizeUsedCmd::runCommand(SocketClient *cli,
		}

		int id = atoi(argv[1]);
		if ((id < LOG_ID_MIN) \|\| (id >= LOG_ID_MAX)) {
		if ((id < LOG_ID_MIN) \|\| (LOG_ID_MAX <= id)) {
		cli->sendMsg("Range Error");
		return 0;
		}

logd/FlushCommand.cpp

+5 −6

Original line number	Diff line number	Diff line
		/*
		* Copyright (C) 2012-2013 The Android Open Source Project
		* Copyright (C) 2012-2014 The Android Open Source Project
		*
		* Licensed under the Apache License, Version 2.0 (the "License");
		* you may not use this file except in compliance with the License.
		@@ -15,11 +15,12 @@
		*/

		#include <stdlib.h>
		#include <private/android_filesystem_config.h>

		#include "FlushCommand.h"
		#include "LogBufferElement.h"
		#include "LogTimes.h"
		#include "LogCommand.h"
		#include "LogReader.h"
		#include "LogTimes.h"

		FlushCommand::FlushCommand(LogReader &reader,
		bool nonBlock,
		@@ -80,7 +81,5 @@ void FlushCommand::runSocketCommand(SocketClient *client) {
		}

		bool FlushCommand::hasReadLogs(SocketClient *client) {
		return (client->getUid() == AID_ROOT)
		\|\| (client->getGid() == AID_ROOT)
		\|\| (client->getGid() == AID_LOG);
		return clientHasLogCredentials(client);
		}

logd/LogCommand.cpp

+110 −1

Original line number	Diff line number	Diff line
		/*
		* Copyright (C) 2012-2013 The Android Open Source Project
		* Copyright (C) 2012-2014 The Android Open Source Project
		*
		* Licensed under the Apache License, Version 2.0 (the "License");
		* you may not use this file except in compliance with the License.
		@@ -14,8 +14,117 @@
		* limitations under the License.
		*/

		#include <errno.h>
		#include <stdio.h>
		#include <stdlib.h>

		#include <private/android_filesystem_config.h>

		#include "LogCommand.h"

		LogCommand::LogCommand(const char *cmd)
		: FrameworkCommand(cmd) {
		}

		// gets a list of supplementary group IDs associated with
		// the socket peer. This is implemented by opening
		// /proc/PID/status and look for the "Group:" line.
		//
		// This function introduces races especially since status
		// can change 'shape' while reading, the net result is err
		// on lack of permission.
		//
		// Race-free alternative is to introduce pairs of sockets
		// and threads for each command and reading, one each that
		// has open permissions, and one that has restricted
		// permissions.

		static bool groupIsLog(char *buf) {
		char *ptr;
		static const char ws[] = " \n";
		bool ret = false;

		for (buf = strtok_r(buf, ws, &ptr); buf; buf = strtok_r(NULL, ws, &ptr)) {
		errno = 0;
		gid_t Gid = strtol(buf, NULL, 10);
		if (errno != 0) {
		return false;
		}
		if (Gid == AID_LOG) {
		ret = true;
		}
		}
		return ret;
		}

		bool clientHasLogCredentials(SocketClient * cli) {
		uid_t uid = cli->getUid();
		if (uid == AID_ROOT) {
		return true;
		}

		gid_t gid = cli->getGid();
		if ((gid == AID_ROOT) \|\| (gid == AID_LOG)) {
		return true;
		}

		// FYI We will typically be here for 'adb logcat'
		bool ret = false;

		char filename[1024];
		snprintf(filename, sizeof(filename), "/proc/%d/status", cli->getPid());

		FILE *file = fopen(filename, "r");
		if (!file) {
		return ret;
		}

		bool foundGid = false;
		bool foundUid = false;

		char line[1024];
		while (fgets(line, sizeof(line), file)) {
		static const char groups_string[] = "Groups:\t";
		static const char uid_string[] = "Uid:\t";
		static const char gid_string[] = "Gid:\t";

		if (strncmp(groups_string, line, strlen(groups_string)) == 0) {
		ret = groupIsLog(line + strlen(groups_string));
		if (!ret) {
		break;
		}
		} else if (strncmp(uid_string, line, strlen(uid_string)) == 0) {
		uid_t u[4] = { (uid_t) -1, (uid_t) -1, (uid_t) -1, (uid_t) -1};

		sscanf(line + strlen(uid_string), "%u\t%u\t%u\t%u",
		&u[0], &u[1], &u[2], &u[3]);

		// Protect against PID reuse by checking that the UID is the same
		if ((uid != u[0]) \|\| (uid != u[1]) \|\| (uid != u[2]) \|\| (uid != u[3])) {
		ret = false;
		break;
		}
		foundUid = true;
		} else if (strncmp(gid_string, line, strlen(gid_string)) == 0) {
		gid_t g[4] = { (gid_t) -1, (gid_t) -1, (gid_t) -1, (gid_t) -1};

		sscanf(line + strlen(gid_string), "%u\t%u\t%u\t%u",
		&g[0], &g[1], &g[2], &g[3]);

		// Protect against PID reuse by checking that the GID is the same
		if ((gid != g[0]) \|\| (gid != g[1]) \|\| (gid != g[2]) \|\| (gid != g[3])) {
		ret = false;
		break;
		}
		foundGid = true;
		}
		}

		fclose(file);

		if (!foundGid \|\| !foundUid) {
		ret = false;
		}

		return ret;
		}

logd/LogCommand.h

+4 −1

Original line number	Diff line number	Diff line
		/*
		* Copyright (C) 2012-2013 The Android Open Source Project
		* Copyright (C) 2012-2014 The Android Open Source Project
		*
		* Licensed under the Apache License, Version 2.0 (the "License");
		* you may not use this file except in compliance with the License.
		@@ -17,6 +17,7 @@
		#ifndef _LOGD_COMMAND_H
		#define _LOGD_COMMAND_H

		#include <sysutils/SocketClient.h>
		#include <sysutils/FrameworkCommand.h>

		class LogCommand : public FrameworkCommand {
		@@ -25,4 +26,6 @@ public:
		virtual ~LogCommand() {}
		};

		bool clientHasLogCredentials(SocketClient * cli);

		#endif